I don't plan on changing the cam. I want to do 258 crank and rods and stock 4.0 pistons. If I do bore over it will be .020-.030 and id like to avoid high CR so I can run 87. If that's not possible ill live with running higher octane

waste o money

this will be a gigantic turd 10-20hp at the most increase over stock yea no thanks

Cam, here's what i see. You will do this 4.5 Stroker, then when you decide to go to tons (and countless threads), you'll go to a 5.3. Then after you are on tons, you'll want a 6.0. You are wasting your money. Just swap your motor with a low mile 4.0 or rebuild yours. Keep it cheap and simple. You don't need anything bigger than a 4.0.

Cam, here's what i see. You will do this 4.5 Stroker, then when you decide to go to tons (and countless threads), you'll go to a 5.3. Then after you are on tons, you'll want a 6.0. You are wasting your money. Just swap your motor with a low mile 4.0 or rebuild yours. Keep it cheap and simple. You don't need anything bigger than a 4.0.

i have 200 in a cam and lifters and i am running 93 right now have not tried running 87-89 yet. i have 200 in boring the block, instaling new cam bearings and hot tanking the block. 150 in the head which incudes valve job and decking the head to insure it was straight. 200 in the cank that was turning it to .10 to .10 on main and rod journals and makeing sure it was straight. 80 in injectors from ebay 200 for pistons,rings,and cam bearings. 100 in main and rod bearings and 90 in a oil pump. if u are gonna do a rebuild i would most defintly put new cam bearings in it. if i wereto do it all over again i would save the moiney fro the stroker and just go 5.3 in it. or find a good running 4.0

Ya I'm not looking to spend that much. New can bearings even when my motor only has 115k on it?

Quote:

Originally Posted by Cartman

waste o money

this will be a gigantic turd 10-20hp at the most increase over stock yea no thanks

For $300 more id be ok with 20hp

Quote:

Originally Posted by 8PTBUCK

Cam, here's what i see. You will do this 4.5 Stroker, then when you decide to go to tons (and countless threads), you'll go to a 5.3. Then after you are on tons, you'll want a 6.0. You are wasting your money. Just swap your motor with a low mile 4.0 or rebuild yours. Keep it cheap and simple. You don't need anything bigger than a 4.0.

I may go to a 5.3 eventually but while rebuilding it why not spend $300 or so more to get a little more pep. It will be cheap and simple I'm not as cheap as you

I am running a stroked 4.0.. 4.2 crank and rods .030 over pistons I decked the block and milled the head .010 each, 440 lift custom ground cam and a 99 intake with venom 26 lb. injectors and a 62 mm throttle body with a 1.5 inch spacer.. I have tons of power but I have to run premium in the summer and can run midgrade in the winter.. as far as mileage when I first installed it I was getting 21 mpg on the highway with my ax15 ,3.55 gears and 33s.. and that was with stock throttle body since then I am running 4.10s and 33s now I am only getting 12.5 on the highway with the 62 mm .. its all in a 1991 xj 2door.. if you do build it make sure to watch your numbers I am at 10.5:1 compression ratio and I wish it was lower... but that was my own miscalculation but I would give up the power for anything.. I do most of my climbing barley touching the throttle and on the street I have guys thinking I am running a v8 because of how well it gets up and moves.. I wish you luck on a build

I have done a huge amount of research on strokers, assembled one and I can tell you there is a lot of misinformation and second hand knowledge out there. There are also a lot of poorly built but still running strokers from what I have gathered. The biggest issue you will have is compression ratio. To get proper quench, you need to mill the deck of the block, which raises CR. Too high of a CR is what necessitates higher octane fuel. Basically you have two options to lower your CR. First is custom pistons, I believe Keith Black makes a set, second is having stock pistons dished deeper. Most people don't dive this deep into the build, build a motor with crappy quench and end up unhappy. If you have questions go to Jeepstrokers.com and start reading...more info there than you can imagine, most of which I've forgotten.

Why do you need more power when I'm crawling the same hills with my 2.5?

edit: just gear it

I need to rebuild it just thinking about making a lil more power while in there

Quote:

Originally Posted by dew jeep

I am running a stroked 4.0.. 4.2 crank and rods .030 over pistons I decked the block and milled the head .010 each, 440 lift custom ground cam and a 99 intake with venom 26 lb. injectors and a 62 mm throttle body with a 1.5 inch spacer.. I have tons of power but I have to run premium in the summer and can run midgrade in the winter.. as far as mileage when I first installed it I was getting 21 mpg on the highway with my ax15 ,3.55 gears and 33s.. and that was with stock throttle body since then I am running 4.10s and 33s now I am only getting 12.5 on the highway with the 62 mm .. its all in a 1991 xj 2door.. if you do build it make sure to watch your numbers I am at 10.5:1 compression ratio and I wish it was lower... but that was my own miscalculation but I would give up the power for anything.. I do most of my climbing barley touching the throttle and on the street I have guys thinking I am running a v8 because of how well it gets up and moves.. I wish you luck on a build

Good to know. Thanks

Quote:

Originally Posted by wakeboard76

I have done a huge amount of research on strokers, assembled one and I can tell you there is a lot of misinformation and second hand knowledge out there. There are also a lot of poorly built but still running strokers from what I have gathered. The biggest issue you will have is compression ratio. To get proper quench, you need to mill the deck of the block, which raises CR. Too high of a CR is what necessitates higher octane fuel. Basically you have two options to lower your CR. First is custom pistons, I believe Keith Black makes a set, second is having stock pistons dished deeper. Most people don't dive this deep into the build, build a motor with crappy quench and end up unhappy. If you have questions go to Jeepstrokers.com and start reading...more info there than you can imagine, most of which I've forgotten.

Will my quench and CR be fine with just putting in a 258 crank and rods I don't want to do pistons unless I have to. If I do this will I need special head gaskets?

Just do a stock rebulid with a little more bumpstick and spend your cash on the head. The best bang for the buck is head work. Power comes from the head and intake. The more air / fuel you can move = more power. Or save the cash do a stock rebulid and regear your ride.

If you have to rebuild your engine, why all the hate against trying to bump the HP a bit?

Picking up someone elses 4.0L seems like a gamble to me, you don't know its history. Stuffing another engine in it seems like a headache, your still left with someone elses engine plus everything behind it might not be up to it.

I have plans to stroke my 4.0L in the future as well, refresh it and get a little more out of it. I hope thread gets back on track....

Just do a stock rebulid with a little more bumpstick and spend your cash on the head. The best bang for the buck is head work. Power comes from the head and intake. The more air / fuel you can move = more power. Or save the cash do a stock rebulid and regear your ride.

X1558833558658566

Spend that $300 on a cam and headwork. I run a comp cams extreme 4x4 in my I6 along with a good valve job and love it.

Better yet, cam, get head rebuilt and then gasket match all the intake/ exhaust ports yourself with a $35 grinder set.